First, make sure the water source and electricity source are connected and working. Second, check the back of your unit to see if the pads are damp. Adjust the water flow. For the evaporation process to occur, the pads must be damp before you turn on the fan. Third, make sure there is water in the tank. It should be allowed to fill before you turn the pump on. Fourth, if none of these options fix the problem, contact our Tech Support Dept.